Process for the preparation of sulfonated detergent composition



United States Patent 3,488,384 PROCESS FOR THE PREPARATION OF SULFO- NATED DETERGENT COMPOSITION Adriaan Kessler, Cincinnati, and Phillip F. Pflaumer,

Colerain Township, Hamilton County, Ohio, assignors to The Procter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Continuation-in-part of application Ser. No. 516,081, Dec. 23, 1965, which is a continuation-in-part of application Ser. No. 423,292, Jan. 4, 1965. This application June 29, 1966, Ser. No. 561,352

Int. Cl. C07c 143/10, 143/16; C07d 89/00 US. Cl. 260-513 5 Claims ABSTRACT OF THE DISCLOSURE Process for preparing an organic water-soluble sulfonated reaction product having valuable detergent prop erties which comprises reacting alpha olefin hydrocarbons (C with 1.001 to 1.15 moles per mole of olefin of uncomplexed S0 to form an acid mix of particular composition, immediately hyperalkalizing the acid mix by vigorously mixing it with an aqueous alkali solution in an amount sufficient to provide and maintain a pH in excess of 7 throughout the hyperalkalization and subsequent saponification steps and, directly thereafter, saponifying the hyperalkalized acid solution at a temperature of from about 220 F. to about 400 F.

This application is a continuation-in-part of copending application Ser. No. 516,081, filed Dec. 23, 1965, now abandoned, which was a continuation-in-part of application Ser. No. 423,292, filed Jan. 4, 1965, now abandoned.

This invention relates to an, improved process for the preparation of an organic water-soluble sulfonated reaction product which has valuable detergent properties and is thus useful as a detergent composition.

While sulfonated detergent compounds and processes for their preparation have been known and used for many years, there is a continuing need and demand for improved processes and products. Few of the known processes have been completely successful in meeting the rigid requirements of economics and performance results imposed by the soap and detergent industry. For instance, while some sulfonation processes claim to provide detergent products of high quality, they are generally diflicult to control and are inordinately costly. The prod nets of these reactions are frequently expensive, as a result of which, such processes have not found wide commercial acceptance in the industry since the economic factor is so important. Yet other processes, which reputedly solve the problem of cost, are subject to the objection that they produce reaction products of generally inferior quality. Still other known processes have limitations in that while they offer quality products at a reasonable cost, they cannot be scaled up to satisfy production line requirements of a uniform high quality product.

Accordingly, it is a primary and major object of the present invention to provide an improved process for the preparation of an organic water soluble sulfonated reaction product which has outstanding detergent prop erties. Another object is to provide such an improved process which is inexpensive and which also is easy to perform. A further object of the present invention is to provide a process for the conversion of alpha olefin hydrocarbons into valuable detergent compositions, which process can be readily scaled up to factory requirements with a minimum of effort and without an adverse eflfect on cost factors or sacrifice to the uniform high quality of the reaction product. Yet another object of the present invention is to provide an inexpensive, continuous process 3,488,384 Patented Jan. 6, 1970 for the preparation of a sulfonated alpha olefin reaction product having valuable detergent properties which process mcludes in its essential sequence of steps, hyperalkalizing a preformed sulfonation reaction product and, thereafter, saponifying the hyperalkalized mixture to obtain the desired improved detergent compositions. Other objects will become apparent from the following detailed description of the present invention.

' According to the present invention the foregoing ob ects are accomplished by reacting acyclic alpha-olefin hydrocarbon raw materials containing from about 10 to about 26 carbon atoms with uncomplexed vaporus sulfur trioxide to form a sulfonated reaction product, immediately hyperalkalizing said sulfonated reaction product to form a mixture containing neutralized olefin sulfonate salts, sultone inner esters described below, and difunctional compounds also described below, and thereafter, saponifying said mixture to form the desired product havmg outstanding detergent properties.

The sulfonation reaction can be carried out according to any known batch or continuous sulfonating processes including, as examples, vacuum sulfonation, air-dilution sulfonation, or film reactor sulfonatin-g systems. The primary requisite of the sulfonation reaction is that it should produce a sulfonated reaction mixture which comprises a mixture of a protonic acid species and sultone inner esttlers corresponding to the alpha olefin starting materra s.

A major portion of the protonic acid species is comprised of positional isomers of alkene-l-sulfonic acids. The protonic acid species can also contain polyfunctional compounds which are alkene disulfonic acids and sultone sulfonic acids.

The chain length of each of the compounds in the sulfonation reaction mixture corresponds to the chain length of the starting alpha-olefins.

The sultone inner esters present in the sulfonation acid mix of the present invention contain at least five atoms in the cyclic group in order for the final composition to possess the desired detergency performance characteristics.

The formation of a sulfonation reaction product (also referred to in the art as an acid mix) having the foregoing composition requires the use of an uncomplexed vaporous sulfur trioxide gas as a sulfonating agent. If a complexed sulfur trioxide sulfonating agent is employed such as sulfur trioxide complexed with tertiary butyl amine, dioxane, pyridine, and the like, the mechanism necessary for the present invention is substantially interfered with and the result is that the desired detergent properties are not obtained.

The alpha-olefin raw materials can contain from about 10 to about 26 carbon atoms, and preferably from 12 to 20 carbon atoms. Mixtures of hydrocarbons having carbon atoms in these ranges can be employed also. Olefins having the chain lengths in these ranges are generally in liquid form. Chain lengths above about 18 carbons may be solids and these are melted before used in the present invention. Liquid olefins represent a preferred embodiment herein.

Alpha-olefins can be used which are derived from any convenient processes, for example, wax cracking, ethylene buildup and by dehydrating the primary alcohols obtained by hydrogenating fatty acids or their esters, e.g. those obtained from palm oil, tallow, coconut oil and olive oil. Vinylidene branching which occasionally occurs as a by-product in some preparative methods seems to olfer no serious problems to the present invention. The present invention can tolerate amounts of Vinylidene branched olefins in the starting material up to levels of about 10%, or even more. Although these by-products do not interfere with the sulfonation reaction, it is nevertheless a preferred embodiment of the present invention to run the sulfonation reaction with alpha olefins wherein the vinylidene branched compounds are held to a minimum.

Alpha-olefins which can be used in the present invention include l-decene, l-undecene, l-dodecene, l-tridecene, l-tetradecene, l-pentadecene, l-hexadecene, l-heptadecene, l-octadecene, l-nonadecene, l-eicosene, l-heneicosene, l-docosene, l-tricosene, l-tetracosene, l-pentacosene, and l-hexacosene. Mixtures of these compounds can also be used.

The sulfur trioxide sulfonating agent used in the present invention is used as a gas reactant. It can be used alone or along with a diluent such as any of the commonly used inert materials, e.g. nitrogen, air, etc. When used in a diluted form, the volumetric ratio of diluent to sulfur trioxide should be in the range of from about 10:1 to about 100: 1, and preferably within a range of about 15:1 to about 75:1.

The sulfur trioxide can be derived from any convenient source, for example, from the burning of sulfur, or from conventional oleum stripping. Stabilized sulfur trioxide can be used, also, but the particular stabilizing agent such as tertiary butyl phosphate, boron and phosphorous compounds, represents a non-essential compound to the reaction system. If stabilized sulfur trioxide is used in the present process the stabilizing agent eventually should be removed from the sulfur trioxide before it is added to the reaction system. As mentioned previously, the sulfonating agent cannot be of the commonly used complexed variety. No complexing agent which is known and which has come into general usage up to the present time has been found suitable for use in the present invention. The reason for this is thought to be that the complexing agent initiates a different reaction mechanism which interferes with the desired reaction system. This is evidenced by the fact that a sulfonated acid mix prepared with a complexed sulfur trioxide sulfonating agent is different from an acid mix prepared with an uncomplexed sulfur trioxide sulfonating agent. The use of the latter is essential to the present invention. While not wishing to be bound by any theory as to the peculiar behavior of complexed sulfur trioxide, it is thought that the presence of a comlexing agent leads to the formation in the system of appreciable quantities of 2-hydroxyalkyl-l-sulfonic acids. These compounds, after neutralization, are not especially useful as detergents at ordinary washing temperatures. Uncomplexed gaseous sulfur trioxide leads, on the other hand, to the preparation of appreciable quantities of 3-, 4- and S-hydroxyalkyl-l-sulfonic acids which, in neutralized form it has been discovered, are excellent detergent materials. At the same time, use of uncomplexed sulfur trioxide inhibits or holds down the amount of the undesirable 2-hydroxyalkyl-l-sulfonic acid prepared. The adverse behavior of the complexed sulfur trioxide is due, it is thought, to the complexing agent adding on to the carbonium ion of the hydrocarbon molecule. This seems to have the effect of preventing ionic migration along the aliphatic chain. Thus, the use of a complexed sulfur trioxide interferes with the present invention in at least two ways: (1) by favoring the formation of undesirable amounts of Z-hydroxyalkyl-l-sulfonic acids and, (2) inhibiting the formation of the desired water soluble 3- hydroxy, 4-hydroxy and 5-hydroxyalkyl-l-sulfonic acids of the present invention. It is described in detail hereinafter.

The proportions of the sulfur trioxide sulfonating agent to the alpha-olefin raw material employed in carrying out the sulfonation reaction can vary within relatively Wide limits ranging from less than stoichiometric amounts to stoichiometric amounts, to an excess of the sulfonating agent. It is preferred, however, to run a sulfonation reaction in which a molar excess of sulfonating agent is used. The molar excess can range from about .1% to about 15% and, preferably from about 2% to about 8% of the sulfonating agent, over the alpha-olefin or, in other words, the molar ratio of uncomplexed vaporous sulfur trioxide to alpha-olefin should be from about 1.00121 to about 1.15:1. A preferred molar ratio is from about 1.02:1 to about 1.08:1.

In addition to the respective amounts of sulfur trioxide and olefin hydrocarbon employed, the rate of mixing the gaseous uncomplexed sulfur trioxide sulfonating agent and the liquid alpha-olefin is also important. The rates of addition for each reactant can vary according to the specific sulfonating process. It has been found, however, that for batch sulfonation processes involving vacuum sulfonation and air-dilution techniques, a preferred range for the rate of addition should be between 3.5 10 to about 2.1 10 pounds of sulfur trioxide per pound of liquid olefin per minute. If less than the prescribed rates are used, the reaction will require an inordinately long time resulting in a deterioration in the color of the sulfonated acid mix. If the prescribed rates are exceeded, the yield of the desired olefin sulfonate reaction product will be lowered and the color will be adversely affected due to the tendency of having localized high concentrations of sulfur trioxide.

When a batch vacuum sulfonation process is being performed it is necessary that the absolute pressure within the system be maintained at less than about 100 millimeters. When an air-dilution sulfonation process is being performed the absolute pressure within the system can range from a partial vacuum of about 400 millimeters to an absolute pressure well above atmospheric pressures.

The temperature at which the sulfonation reaction takes place depends largely on the nature of the reactants and the different processing systems which can be employed. Under ordinary conditions, however, the sulfonating temperatures can range from about 32 F. to about 180 F. but should preferably be within the range of about F. to about F. At temperatures below about 32 F., problems can arise involving the solidification of the starting alpha-olefin raw materials together with other problems which may require special apparatus. Allowing the temperature to exceed about F. causes a discolored and generally inferior reaction product.

The length of time for conducting the sulfonation reaction will vary within relatively wide limits also depending on the different sulfonating systems used. The shortest sulfonation reaction time will be that involved in a film sulfonator in which the reaction is almost instantaneous and in these instances a sulfonating time of from a few seconds to a few minutes is preferred, e.g. from about ten seconds to about 5 minutes. In batch sulfonators, longer times are usually necessary and a minimumoperable time is on the order of about 5 to 10 minutes while a maximum time is on the order of several hours, e.g. from about 1 /2 to about 3 or 4 hours. Longer times can be used but there is little advantage in doing so since the risk of forming undesirable by-products increase also.

It is important in the sulfonation reaction to provide for rapid contact between the gaseous phase of the sulfonating agent and the liquid phase of the sulfonatable material. This is less of a problem in film-type reactors and air-dilution systems where highly rapid and eflicient contact can be obtained between the gaseous sulfonating agents and the sulfonatable olefin hydrocarbon. In batch processes, however, an artificial means is usually necessary to obtain good contact between the gaseous sulfonating agent and the liquid sulfonatable hydrocarbon. This is usually accomplished by incorporating into the reaction system mechanical stirring or agitating means which are well known in the art. The sulfonation reactions described above are preferably conducted under substantially anhydrous conditions.

According to the present invention, the reaction product of the sulfonation step, also referred to as the acid mix, consisting essentially of about 30% to about 70% alkene-l-sulfonic acids, about 20% to about 70% sultone inner esters having not less than five atoms in the cyclic group, and a minor amount of about 2% to 15% of highly polar polyfunctional disulfonated compounds, is immediately hyperalkalized. For purposes of describing the present invention, the term hyperalkalized is used to describe that step which, according to the present invention, immediately follows the completion of the sulfonation step described above. In order to accurately describe the present invention in the simplest terms and, at the same time, to distinguish the present process from unrelated prior art sulfonation processes, it was necessary to use a new descriptive term which takes its meaning from the fundamental concept and discovery of the present invention. The full meaning of the expressions such as hyperalkalizing or hyperalkalized, as used herein, will be readily apparent from the following description.

The hyperalkalization step of the present process embodies immediately mixing the sulfonated acid mixwith an aqueous alkali solution consisting of any strongly basic compound such as sodium hydroxide, potassium hydrox ide, ammonium hydroxide, the corresponding oxides, carbonates and the like, or triethanolamine or substituted ammonium hydroxides in order to simultaneously neutralize the protonic acid species in the acid mix and also establish a residium of alkali for use in the subsequent saponification step. The protonic acid species are those reaction products in the acid mix which contain a free sulphonic acid group in the molecule and include the protonic alkene-l-sulfonic acids, the alkene disulfonic acids, and the sultone sulfonic acids.

The critical timing associated with the hyperalkalizing step is an essential aspect of the present invention. It should follow the sulfonation reaction immediately. This is discussed in greater detail below. The sulfonated acid mix is mixed during the hyperalkalizing step with from about 1.0 to about 1.3 moles equivalent of alkali per mole of reacted sulfur trioxide. The amount of alkali which is required to carry out the hyperalkalization step is that amount which is capable not only of neutralizing the proton bearing components of the acid mix, but also, of establishing a residium of alkali sufficient to completely neutralize immediately the additional proton bearing acid species which are formed in the subsequent saponification step. Thus, the hyperalkalization step embodies an acidbase neutralization reaction but also includes the embodiment of establishing a residium of alkali which is required for the subsequent saponification step. The necessity for having the alkali residium established prior to the initiation of the saponification step is described fully hereinafter. This residium amounts to about 0.2 to about .9 mole of alkali based on the reacted sulfur trioxide.

The aqueous alkali solution should contain the required amount of alkali in a concentration of from about 1/ mole per liter to about 3 moles per liter of solution.

The temperature during the hyperalkalizing step should be in the range of from about 32 F. to about 215 F. and preferably between about 80 F. to about 170 F. The hyperalkalizing step is slightly exothermic so the temperature can be expected to rise slowly throughout this range.

The duration of the hyperalkalization step can be determined :by a periodic analysis of the hyperalkalized acid mix. The proton bearing species in the reaction product of the acid mix will be neutralized rapidly when brought in contact with the alkali material. The hyperalkalization step terminates when all the proton acid species are neutralized leaving the residium of alkali available for the following saponification step. The time required for this reaction will usually be predetermined based on the amount of reactants used and the specific processing technique employed. Usually this step requires from several seconds to about two hours, and preferably from about 30 seconds to about 30 minutes.

It has been discovered according to the present invention, as mentioned above, that the hyperalkalization step should immediately follow the completion of the sulfonation reaction. For purposes of the present invention, the term immediately is intended to mean that the sulfonated acid mix should be mixed with the aqueous alkali solution as rapidly as is practically possible, and, in any event, within a few seconds, for instance, from about 2 seconds to about 15 minutes after the completion of the sulfonation reaction. This requirement is tied in closely with the discovery that failure to quickly render the acid mix alkaline results in the formation of undesirable color bodies, and equally as important, the formation of undesirable by-products. It has been discovered that isomerization of the sultone inner esters present in the acid mix tends to occur if the acid mix is allowed to become quiescent for any substantial length of time causing the gamma sultone ester compounds to isomerize to the delta sultone esters. The delta sultone esters are considerably more difiicult to saponify than the gamma sultone esters. If the isomerization from the gamma sultone to the delta sultone occurs, substantially more vigorous and expensive conditions need to be used during the saponification step. Accordingly, it is a preferred embodiment of the present invention to immediately hyperalkalize the acid mix, and thus inhibit or prevent the formation of undesirable color bodies and minimize the isomerization of the gamma sultones to other sultone ester forms which are more difficult to convert to high quality detergent compounds.

It has also been discovered that there is an additional and important consideration involved in hyperalkalizing a sulfonation reaction acid mix prepared by a film sulfonation process. The resulting acid mix from a film sulfonation reaction contains a large amount of precursors of Z-hydroxyalkyl-l-sulfonic acid. It has been pointed out above that this compound is not a good detergent, and it is regarded as an undesirable reaction product Whose presence in the final product is to be held to an absolute minimum. This is accomplished according to a preferred embodiment of this invention by subjecting the film sulfonation reaction acid mix to an aging step of from about 2 minutes to about 15 minutes prior to the hyperalkalization step, and preferably from about 4 minutes to about 13 minutes. The purpose of the aging step is to allow time for ionic migration of the precursors of 2-hydroxyalkyll-sulfonic acids to precursors of more internal hydroxyalkyl-l-sulfonic acids, such as, for example, 3-hydroxyalkyl-l-sulfonic acid. Thus, by introducing an aging step having a critical prescribed duration, it is possible according to this invention to prepare a reaction product from a film sulfonation reaction acid mix which contains a minimum amount of 2-hydroxyalkyl-l-sulfonic acids as Well as a minimum amount of delta sultone esters which, as mentioned earlier, are more difficult to saponify than are gamma sultone esters.

The aging step comprises holding the film sulfonation acid mix for from about 2 minutes to about 15 minutes, preferably from about 4 minutes to about 13 minutes, at the temperature at which the film sulfonation reaction is conducted. Film sulfonation reaction temperatures usually are in the range of from about F. to about 180 F., and more preferably from F. to about F. These are also the applicable temperature ranges for the required aging step in treating film sulfonation reaction acid mixes.

An aging step is not necessary in conjunction with other sulfonation reactions which involve larger reaction times than those ordinarily associated with a film sulfonation system. The longer reaction times serve the purpose of the present aging step and thereby take into account the desired ionic migration mentioned above.

It has not been realized heretofore that the quality of detergent compounds derived from sulfonated alphaolefins is substantially deteriorated if an inordinately long time lapse occurs intermediate the sulfonation step and the neutralization step. Evidence of the lack of appreciation of this problem is the fact that some acid mix manufactures even allow for or specifically provide for the storing of sulfonated acid mixes for substantial periods of time after the sulfonation reaction. Some, presumably without recognizing the regradation which can occur, even ship and sell such acid mixes.

It is a preferred embodiment of the present invention of performing the hyperalkalization step by adding the sulfonation reaction product to the aqueous alkali solution. The temperature of the alkali solution is not critical since the acid mix is at a sufficiently high temperature to initiate the neutralization reaction which occurs as part of the total hyperalkalizing step.

It is within the scope of the present invention to have the sequence of addition reversed with the alkali solution being added to the sulfonated acid mix. Any such variation of the process, however, will have to take into account the viscous nature of the acid mix and may require the use of solvents. As previously mentioned, the concentration of the alkali in the neutralizing solution is to be between about A mole per liter to about 3 moles per liter. This concentration insures that the alkali mixture is maintained in a fluid consistency for ease of handling.

It is sometimes necessary to provide for good mixing between the olefin sulfonate acid mix and the alkali solution by mechanical means. The agitation affords good contact between the acid species and the alkali salts causing immediate neutralization of the sulfonic acids. The mixing can be affected by any convenient manner SUCh as mechanical stirring and external cooling loops.

It has been mentioned that the proton bearing sulfonic acids in the acid mix are neutralized upon contact with the alkali. A small amount of the sultone inner esters such as the gamma sultones is also neutralized to the corresponding hydroxyalkyl-l-sulfonates and the alkene sulfonates. It is though that of the small amount of sultones Which are neutralized in the hyperalkalization step, about 70% to about 90% is converted to the corresponding hydroxy sulfonates and about to about 30% is converted to the corresponding alkene sulfonates. This amount, however, is negligible and for the most part the major portion of the sultone esters do not enter into the hyperalkalization reaction but are primarly dealt with in the following saponification step.

The hyperalkalized solution contains a mixture of water soluble salts of the sulfonated alkene double b nd positional isomers and the salts of the polyfunctional compounds previously described as well as the sultone inner esters having at least five atoms in the cyclic group, and the residium of alkali which is established during the hyperalkalizing step.

The next step of the present invention calls for heating said hyperalkalized solution to a temperature within a range of from about 220 F. to about 400 F., and preferably from about 250 F. to about 325 F.

The primary purpose of this high temperature conditioning step in the process is to initiate the saponification reaction and thereby convert the sultone inner esters containing at least five atoms in the cyclic group, which are not detergent compounds, to corresponding hydroxyalkyl-l-sulfonate compounds and alkene-l-sulfonate compounds which do have excellent detergent properties. For instance, the gamma-sultone esters are saponified in the alkaline system to 3-hydroxyalkyl-1-sulfonates and the delta-sultone esters upon saponification in the alkaline system yield 4-hydroxyalkyl-l-sulfonates, as well as the respective alkene-l-sulfonate compounds.

What appears to occur in the saponification step is that the cyclic ester group is cleaved and the free bonds react immediately with the residium alkali which is present due to the preceding hyperalkalizing step. By this reaction the non-detergent sultone inner ester compounds are converted to valuable detergent salt forms, i.e. the hydroxyalkyl-l-sulfonate and the alkene-l-sulfonates.

The time required for the saponification to take place to the desired completeness level ranges from about tWo minutes up to about three hours. It has generally been found, however, that saponification reaction lasting from three minutes up to two hours is preferred and offers excellent results.

It is important that the pH of the reaction mixture during the saponification reaction be maintained in an alkaline pH range, i.e. in excess of about 7 throughout the reaction. If the pH of the solution is allowed to drop even briefly into an acid range, acid hydrolysis can be initiated which causes the formation of considerable color bodies and other undesired by-products. The point to be emphasized is that if the pH during saponification becomes acid even for a short period, the quality of the reaction product can be seriously deteriorated.

According to a preferred embodiment, the saponification step should directly follow the hyperalkalizing step. In the context of the preferred embodiment, the term directly means that the saponification step should be understaken promptly upon completion of the hyperalkalizing step. In a continuous process according to this invention the hyperalkalized solution passes directly to a heating zone such as a heating coil where the temperature is effectively and promptly raised to the necessary level. In batch processes, a delay of a few minutes, depending on the specific apparatus arrangements can 'be tolerated, or would normally occur. As mentioned, the saponification step should be initiated directly after the hyperalkalization step and in any event preferably within a few seconds to about 15 minutes after completion of the hyperalkalization step. Some of the examples presented below illustrating a preferred embodiment describe the saponification step as immediately following the hyperalkalization step.

Another important reason for having the saponification step directly follow the hyperalkalizing step is that the sultone inner esters tend to cause a phase separation problem in the hyperalkalized reaction mixture. If the hyperalkalized reaction mixture is allowed to remain undisturbed at temperatures less than 200 F., the sulfone inner esters tend to agglomerate and separate out from the solution. If this happens, a highly complex phase separation occurs with the sultone inner esters forming one layer and the olefin sulfonate detergents forming another layer. This is not by any means a clean and distinct separation of layers. Analyses show that both layers are complex heterogeneous mixtures of several sulfonated reaction products. Although the sultone inner esters can thereafter still be saponified to yield detergent compounds, the yield of such products is markedly re duced, additional mixing steps are required, and the saponification step requires substantially more vigorous processing conditions. The complications caused by the phase separation makes the process substantially more expensive and, therefore, much less desirable. Thus, it is preferred according to the present invention to keep the hyperalkalized reaction product in a single phase system by appropriate control of temperature and agitation.

The sulfonated alkene positioned isomers which are neutralized during the hyperalkalization step generally are not affected by the saponification step. The present invention is, however, designed to take advantage of their presence as surface active agents during said saponification step. At the conclusion of the hyperalkalization step, the sultone inner esters are distributed in the alkaline solution and the sulfonated alkene positioned isomers, which are surface active compounds, tend to maintain this distribution, thereby facilitating the saponification step.

An important consideration in the temperature and duration of the saponification step is that there can occur a competing set of reactions induced by the alkalinity of the solution and the high temperature used. For example, if the specifically prescribed conditions of the present invention are not employed, the desired cleavage of the sultone esters and neutralization of resulting prodnote will begin to occur simultaneously with the undesired formation of color bodies and the degradation of the olefin sulfonate surfactants.

The following examples serve to illustrate the present invention. All percentages, unless otherwise indicated, are by weight.

EXAMPLE I 300 grams of l-hexadecene derived from the'polymerization of ethylene were placed in a vacuum reaction vessel and the pressure was reduced to 10 mm. Hg absolute. 117.8 grams of undiluted uncomplexed sulfur trioxide vapors were bubbled into the reactor with strong agitation over a period of about 30 minutes. During this time the temperature was maintained at 9496 F. and the pressure was held at 10 mm. Hg absolute. A 300 gram aliquot of this mixture comprising protonic alkene sulfonic acid species, sultone inner esters having not less than five atoms in the cyclic group, and polyfunctional compounds which are alkene disulfonic acids and sultone sulfonic acids was immediately hyperalkalized by passing it directly with rapid agitation into an alkali solution of 43.5 grams of sodium hydroxide in 1274 grams of water. The temperature ranged between 120 F. to 130 F. Stirring was continued for 30 minutes at this temperature while the reaction system remained an alkaline system. The mixture was then immediately saponified by raising the temperature to 350 F. and holding the elevated temperature for 1 hour. The mixture was stirred continuously during the saponification reaction and the system remained alkaline throughout. Analysis indicated that the saponified product had gone to a 95.6 weight percent completeness. There was no sultone inner ester remaining in the product. The product consisted of about 65% of a mixture of hexadecene sulfonate positional isomers, about 10% of a mixture of hexadecene disulfonates and hydroxy hexadecane disulfonates, and about 25% of a mixture of predominantly 3-, 4-, and 5- hydroxy hexadecane sulfonates. Performance studies established that the reaction product was an exceptionally good performing detergent composition in the areas of cleaning and whiteness maintenance evaluation.

EXAMPLE II To 300 grams of the l-hexadecene raw material used in Example I was added 123.2 grams of uncomplexed sulfur trioxide vapor following the same procedure described in Example I. The reaction was carried out at a pressure of mm. mercury absolute, a temperature of 120 F., and the sulfur trioxide was added over the period of 30 minutes at a constant rate. 300 grams of the acid mix so prepared and comprising a major proportion of proton bearing alkene sulfonic acids and sultone inner esters having not less than five atoms in the cyclic group, and a minor proportion of polyfunctional compounds which are alkene disulfonic acids and sultone sulfonic acids was then hyperalkalized by adding it, with strong stirring, to 217.5 grams of 20% aqueous sodium hydroxide which had been previously mixed with 1100 grams of distilled water and the solution was then heated to a temperature of 195 F. The temperature rose to 200 F. and was maintained at this level for 30 minutes. The temperature of the mixture was then quickly raised to 310 F. in order to initiate the saponification step and held at that temperature for 1 hour. The pH of the reaction system remained in excess of 7. After the material had cooled, it was analyzed and was found to have a reaction completeness of 91.9 weight percent comprising about 62% of a mixture of hexadecene sulfonate positional isomers, about 30% of a mixture predominantly of 3-, 4-, and 5-hydroxy hexadecane sulfomates, and about 8% of a mixture of hexadecene disulfonates and hydroxy hexadecane disulfonates. The recovered reaction product was water soluble and performed as an outstanding detergent composition especially in the areas of soil removal and whiteness maintenance.

EXAMPLE III 300 grams of l-dodecene derived from the dehydration of the corresponding fatty alcohol was reacted with uncomplexed sulfur trioxide vayor at a temperature of 70 F. passing in 157 grams of sulfur trioxide. The procedure of Example I was followed. The addition of the sulfur trioxide took 35 minutes, while the pressure in the system was maintained at near 20 mm. mercury absolute. As the sulfur trioxide was added the mixture turned in color from colorless to yellow to orange to brown-black. After the sulfur trioxide addition was completed 210 grams of the mixture was immediately hyperalkalized by adding the reaction product to an alkali solution consisting of 552 grams of water and 183 grams of 20% sodium hydroxide which had been preheated to 140 F. Mixing was continued for 15 minutes during which time the material turned to a creamy color. The material, while being stirred, was then directly heated to a temperature of 350 F. in an alkaline system; the temperature was maintained for 10 minutes. Analysis of the product, which was an outstanding water soluble detergent composition, indicated that a 98.5 weight percent completeness had "been obtained.

EXAMPLE IV 250 grams of l-decene derived from the polymerization of ethylene was reacted with 157 grams of vaporized uncomplexed sulfur trioxide according to the procedure described in Example I. The reaction was carried out over a period of 37 minutes at a pressure of 7 mm. mercury absolute and a temperature of about 86 F. Shortly after the reaction began the mixture turned vivid yellow, and then as the reaction progressed, it passed through various shades of orange and red to a final dark brown color. A hyperalkalizing step was carried out immediately by adding 360 grams of the sulfonation reaction acid mixture to an aqueous mixture of 344 grams of 20% aqueous sodium hydroxide and 320 grams of water. The mixture was stirred for about 30 minutes at about F. A final high temperature saponifying reaction was immediately conducted by raising the temperature to 325 F. and holding it for 90 minutes under alkaline conditions. The final product, a light yellow, fluid solution having a completeness of 96.5% was made of approximately 56% of a mixture of isomeric decene sulfonates, about 35% of a mixture of predominantly hydroxy decane sulfonates, and about 9% consisted of various hydroxy substituted decane disulfonates and decane disulfonates.

This reaction product performs satisfactorily as a cleaning agent in built heavy-duty laundering detergent compositions especially when sodium tripolyphosphate and sodium ethane-l-hydroxy-l,l-diphosphonate are used as builders.

EXAMPLE V Using a vacuum reaction system described in Example I, and operated at an absolute pressure of 15 mm. mercury, 150 grams of vaporized uncomplexed sulfur trioxide were reacted with 400 grams of l-eicosene which had been prepared commercially by the dehydration of fatty alcohol. The temperature was gradually increased from 85 F. at the beginning of the run to F. at the end of the run 27 minutes later so as to maintain a fluid condition in the reaction. The material was immediately hyperalkalized with a mixture of 270 grams of 20% sodium hydroxide and 1800 grams water at about room temperature. The mixture was then subjected to a high temperature saponification conditioning step at 270 F. for 2 hours. No acid hydrolysis took place. The product was obtained at 92.9% completeness and was discovered 1 1 to be an excellent detergent in lightand heavy-duty formulations. The detergent is effective in hot water washing solutions and in solid detergent formulations.

EXAMPLE VI 250 grams of l-octadecene derived from C alcohol was reacted with 87.5 grams of uncomplexed sulfur trioxide vapors over a period of 17 minutes at a temperature of about 115 F. to 120 F. and a pressure of 20 mm. mercury absolute, according to the procedure described in Example I. At this point the mixture was dark brown and viscous. Hyperalkalization was carried out immediately at about 50 F. using 275 grams of the sulfonation acid mixture, 249 grams of 20% aqueous sodium hydroxide, 400 grams of ice, and 576 grams of water. After this step the mixture was yellow in color and had a thick, somewhat foamy consistency. A high temperature saponification treatment was carried out for 1 hour at 300 F. The final product has valuable detergent properties.

EXAMPLE VII A sulfonation and hyperalkalization was carried out similar to that described in Example I with the exception that the sulfonation temperature was about 85 F. to 90 F. and the hyperalkalization was carried out at 150 F. Analysis at this point indicated a completeness of 66.2%, with 59.7% of a mixture of alkene sulfonates in the composition. The mixture was then immediately given a high temperature saponification treatment at 325 F. for 2 hours after which the completeness was found to be 93.5% with 65.5% of the composition being alkene sulfonates. The product is an excellent detergent composition EXAMPLE VIII Example I was repeated with the exception that 112.5 grams of uncomplexed sulfur trioxide vapors were added to the l-hexadecene alpha olefin at a temperature of 70 F. The material obtained after the saponification step as described in Example I had a completeness of 92.4% of which 60.5% was a mixture of alkene sulfonates. The product was an excellent performing detergent composition.

EXAMPLE IX A mixture consisting of 60 grams l-dodecene, 120 grams l-tetradecene, and 120 grams l-hexadecene was reacted with 132.5 grams of vaporized uncomplexed sulfur trioxide at a temperature of about 70 F. and a pressure of about 4 mm. mercury absolute in a vaccuum reactor. 400 grams of the reaction acid mix was immediately hyperalkalized at 210 F. for 30 minutes using an alkali solution consisting of 258 grams of 20% sodium hydroxide and 1080 grams of water. The hyperalkalized alkaline mixture was immediately heated to 350 F. and held for 1 hour. The resulting product was an excellent detergent and represented a completeness of 93.4%.

EXAMPLE X Example II was repeated except that the hyperalkalization was conducted at 125 F. and the saponification temperature was conducted at 350 F. A light colored product was obtained which had excellent detergent properties useful in light to heavy-duty formulations such as dishwashing and laundering compositions in liquid or solid formulations.

EXAMPLE XI Example VII was repeated except that the sulfonation reaction was conducted at 95 F. and the hyperalkalization resulted in a completeness of 95.7%. The product can be used as a sole active detergent in complete detergent compositions together with complexing agents, or builders. It can be used also in admixture with other detergent active pounds.

EXAMPLE XII The procedure described in Example II was repeated except that the sulfonation reaction was conducted at F., the hyperalkalization at 50 F., and the final high temperature saponification treatment at 350 F. The result was a product which had a completeness of 95.9% and which can be used advantageously in a wide variety of detergent applications.

EXAMPLE XIII A reaction was carried out between 80 pounds of l-tetradecene derived from the polymerization of ethylene and 34.6 pounds of uncomplexed sulfur trioxide. The sulfonation was carried out in a batch air-dilution sulfonation reactor at a temperature of 114 F. using a 13/1 volume ratio of air to sulfur trioxide vapor and a sulfur trioxide addition rate of 0.5 lb./min. Hyperalkalization was carried out immediately by pumping the sulfonation reaction acid mixture into an alkaline mixture consisting of 32.7 pounds 50 Baum caustic and pounds of water at about F. A high temperature saponification treatment was carried out at 260 F. for 2 hours. The product had a completeness of 93.2%, and possessed valuable detergent properties.

EXAMPLE XIV Example XIII was repeated with the following changes: the sulfonation reaction was conducted at 85 F. with a sulfur trioxide feed rate of 0.3 lb./min. and an air to sulfur trioxide vapor volumetric ratio of 25/1. The product had a completeness of 95.4%, and contained a 58.5% mixture of alkene sulfonates. The product has valuable detergent properties.

EXAMPLE XV An excellent detergent composition was prepared by repeating the procedure of Example XIV but having a sulfonation temperature of 80 F. The product had a completeness of 95.2% and an alkene content of 55.0%.

EXAMPLE XVI Example XIV was repeated at a sulfonation temperature of 110 F. The reaction product had a completeness of 94.2%, an alkene content of 56.3%, and was an excellent detergent composition.

EXAMPLE XVII Example XIV was repeated at a sulfonation temperature of 140 F. The reaction product had a completeness of 91.8%, an alkene content of 58.9, and is an outstanding detergent composition.

EXAMPLE XVHI A film sulfonation reaction acid mix prepared by the film sulfonation process described in copending patent application Ser. No. 514,468, filed Dec. 17, 1965, by Beyer et al. is treated according to the process described herein in order to forestall the formation of undesired 2-hydroxyalkyl-l-sulfonic acid.

Specifically, the sulfonated acid mix prepared by Example IV of the above-identified copending patent application is subjected to an aging step which comprises holding the acid mix obtained from the film sulfonation reaction for 10 minutes at a temperature of F. During this aging step the precursors of Z-hydroxyhexadecane-l-sulfonic acid ionically migrate to precursors of 3- hydroxyhexadecane 1 sulfonic acid, 4 hydroxyhexadecane-l-sulfonic acid, and S-hydroxyhexadecane-l-sulfonic acid. The aged acid mix is then immediately hyperalkalized and saponified according to the procedure described in Example I above. Analysis of the final product following saponification indicates that the product is substantially free of the undesired 2-hydroxyhexadecane-1- sulfonic acid but does contain about 65% of a mixture of hexadecene sulfonate positional isomers, about 25% of a.

mixture of predominatly 3-, 4-, and S-hydroxy hexadecane sulfonates, and about 10% of a mixture of hexadecene disulfonates and hydroxy hexadecane disulfonates. This product is an excellent detergent composition useful in laundering and dishwashing applications.

If the aging step is omitted from this procedure of this example, the final product after saponification contains undesired Z-hydroxyhexadecane-l-sulfonic acid in an amount ranging up to about Such a final product is an inferior detergent as compared to the final detergent obtained by the procedure of this example.

In the proceding examples, sodium hydroxide was used as the alkali ingredient for purposes of hyperalkalizing the acid mix obtained from the sulfonation reaction. The sodium hydroxide can be replaced with equivalent amounts of other strongly alkaline compounds such as potassium hydroxide, ammonium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, triethanolamine, and the like.

The reaction product obtained according to the multistep process described and exemplified above, as has been mentioned, is very useful as a detergent composition. It can be formulated readily into unbuilt, light-built, medium-built, and heavily-built detergent compositions. The lightly-built compositions and the medium-built compositions are especially useful in dishwashing formulations and other compositions prepared specifically for hand laundering delicate fabrics such as silks, cottons, woolens, and others as well as synthetic textile materials such as nylon or the like.

Such applications take advantage of the valuable sudsing characteristics of the compositions prepared by the present invention. Heavily built formulations, moreover, are especially useful for laundering heavily soiled fabrics. The lightly built, medium built, and heavily built compositions discussed above can take the form of liquid compositions embodying also an aqueous vehicle, or solid compositions such as spray dried granules, powders, flakes, tablets and the like.

It is believed that the reaction product prepared according to the process described herein is a highly complex mixture of sulfonate-containing, water-soluble salts of double bond positional isomers of alkene-l-sulfonic acids; bifunctionally substituted sulfur-containing saturated aliphatic compounds where the functional units are hydroxy and sulfonate radicals with sulfonate radicals always being on the terminal carbon and the hydroxyl radical being attached to a carbon atom at least two carbon atoms removed from the terminal carbon atom; alkene disulfonates containing a sulfonate group attached to a terminal carbon atom and a second sulfonate group attached to an internal carbon atom not more than about six carbon atoms removed from said terminal carbon atom, the alkene double bond being distributed between the terminal carbon atom and about the seventh carbon atom; and hydroxy disulfonates which are saturated aliphatic compounds having a sulfonate radical attached to a terminal carbon, a second sulfonate group attached to an internal carbon atom not more than about six carbon atoms removed from said terminal carbon atom, and a hydroxy group attached to a carbon atom which is not more than about four carbon atoms removed from the site of attachment of said second sulfonate group.

The alkene-l-sulfonic acid positional isomers include predominantly alpha beta, beta gamma, gamma delta, and delta-epsilon unsaturated isomers. The bifunctionally substituted sulfur-containing saturated aliphatic compounds are predominantly the 3-, 4-, and S-hydroxy-nalkyl-l-sulfonates. The alkene disulfonates are, preferably, 2 alkene 1,2 disulfonates, 3 alkene 1,2 disulfonates, 4 alkene 1,2 disulfonates, 3 alkene 1,3- disulfonates, 4 alkene 1,3 disulfonates, 5 alkene- 1,3-disulfonates or mixtures thereof. The preferred hydroxy disulfonates are 4-hydroxyalkane-1,2-disulfonates, 5 hydroxyalkane 1,2 disulfonates, 5 hydroxyalkane- 1,3 disulfonates and 6 hydroxyalkane 1,3 disulfonates. The alkane and alkene chain lengths will correspond to the raw materials used, which as mentioned earlier, can contain from about 10 to about 26 carbon atoms. 7 The present invention has been described and illustrated with respect to specific examples. It is understood, however, that modifications and variations which come within the full scope and breadth thereof will be readily apparent to those skilled in the art.

What is claimed is:

1. A process for preparing an organic water-soluble sulfonated reaction product which comprises the steps of:

reacting an acyclic alpha olefin hydrocarbon containing from about 10 to about 26 carbon atoms at a temperature of about 32 F. to about 180 F. and for a time of about 10 seconds to about four hours with about 1.001 to about 1.15 moles per .mole of the alpha olefin of an uncomplexed vaporous sulfur trioxide to form a sulfonated acid mix consisting essentially of from about 30% to about 70% alkene-l-sulfonic acids, about 20% to about 70% sultone inner esters having not less than 5 atoms in the cyclic group, and from about 2% to 15% of polar alkene disulfonic acids and sultone sulfonic acids,

immediately hyperalkalizing said sulfonated acid mix upon completion of the sulfonation step by vigorously mixing said sulfonated acid .mix with an aqueous alkali solution having from 1.0 to about 1.3 moles equivalent of alkali per mole of unreacted sulfur trioxide,

within about 2 seconds to about 15 minutes after the completion of sulfonation thereby quickly rendering the acid mix alkaline having a pH in excess of about 7 and simultaneously neutralizing said alkene sulfonic acids and said polar acids and establishing a residuum of alkali sufiicient to maintain said alkaline condition throughout this step and the following saponification step, the temperature during the hyperalkalizing step being in the range of from about 32 F. to about 215 F., and thereafter directly saponifying said hyperalkalized acid solution comprising a .mixture of (1) water-soluble salts of said alkene-l-sulfonic acids, (2) water-soluble salts of said polar acids, (3) sultone inner esters having at least 5 atoms in the cyclic group, and (4) said residuum of alkali established during the hyperalkalizing step, by heating said hyperalkalized solution to a temperature of from about 220 F. to about 400 F. for a period of from about 2 minutes to about 3 hours,

whereby the cyclic ester group of the said sultone inner esters containing at least 5 atoms in its cyclic group is cleaved and the free bonds react immediately with said residuum of alkali thereby converting said sultone inner esters to water-soluble hydroxylalkyl-l-sulfonates and alkene-l-sulfonates, said byperalkalizing step being preceded by an aging step of from about 2 minutes to about 15 .minutes at a temperature of from about F. to about 180 F. when said sulfonated acid mix is from a film sulfonation reaction.

2. A process according to claim 1 wherein the temperature of the hyperalkalizing step is in the range of from about 80 F. to about F., the time of said hyperalkalizing step is in the range of from about 30 seconds to about 30 minutes,

the temperature of the saponifying step is in the range of from about 250 F. to about 325 F., and the time of said saponifying step is in the range of from about 3 minutes to about 2 hours.

3. A process according to claim 1 wherein the residuum of alkali established during said hyperalkalization reaction amounts to about 0.2 to about .9 mole of alkali based on the reacted sulfur trioxide.

4. A process according to claim 1 wherein said aqueous alkali solution contains alkali in a concentration of from about .1 mole per liter to about 3 moles per liter of Solution.

5. A process for preparing an organic water-soluble sulfonated reaction product according to claim 1 Wherein the sulfonated acid .mix is prepared by a film sulfonation reaction of an alpha olefin hydrocarbon containing from about 10 to about 26 carbon atoms with from about 1.1 to about 1.15 moles per mole of alpha olefin of an uncomplexed vaporous sulfur trioxide and consists essentially of from about to about alkene-lsulfonic acids, about 20% to about 70% sultone inner esters having not less than 5 atoms in the cyclic group, from about 2% to 15% of polar alkene disulfonic acids and sultone sulfonic acids, and up to about 5% of a precursor of 2-hydroxyalkyl-l-sulfonic acid, said film sulfonation reaction being conducted at a temperature in the range of from about F. to about F. for from about 10 seconds to about 5 minutes.

and wherein the hyperalkalizing step is preceded by the step of aging said sulfonated acid mix for from about 2 minutes to about 15 minutes at a temperature of from about 90 F. to about 180 R, whereby during said aging step said precursor of Z-hydroxyalkyl-l-sulfonic acid ionically migrates to form precursors of 3-hydroxyalkyl-l-sulfonic acid, 4-hydroxyalkyl-l-sulfonic acid, and S-hydroxyalkyl-l-sulfonic acid.

References Cited UNITED STATES PATENTS 2,061,618 11/1936 Downing et al. 2605l3 3,164,608 1/1965 Blaser 260513 3,164,609 1/1965 Voss et a1 2-60513 3,255,240 6/1966 Wolfram et al. 260--513 3,259,645 7/ 1966 Brooks et al. 260--5l3 3,409,637 11/1968 Eccles et al. 2'605l3 FOREIGN PATENTS 1,307,710 9/1962 France.

DANIEL D. HORWITZ, Primary Examiner 

